Crystal holder



Nov. 11, 1947. N. A. NELSON 2,430,478

' CRYSTAL HOLDER Filed Nov. 27, 1944 Patented Nov. 11, 1947 2,43 0,478

UNITED STATES PATENT OFFICE CRYSTAL HOLDER Neil A. Nelson, Dayton, Ohio .Appueauo'n November 27, 1944, serial No. 565,384

` claims. (ci. r11-327) (Granted under the act of March 3, 1883, as

The invention described herein may be manufactured and used by or for the Government for governmental purposes. without the payment to me of any royalty thereon. n

The invention-to be hereinafter described relates to crystal holders of the plug-in type for radio operation.

Inuse in radio operation frequent changes of crystals are essential, as when the frequency of a transmitter is shifted, for instance. Repair, renewal and many other causes make, ready lchange'an important consideration. To meet such requirements, crystal holders in plug-in f orm have been developed, facilitating such rapid substitution.

The rapidly. spreading use of radio equipment to many fields includes practically all forms of transportation many of which involve high and frequent vibration and frequent or even constant exposure to dirt. dust, moisture and other damagingv elements or conditions seriously affecting the operation. Penetration of moisture, for instance. may readily become fatal to the operation. Due to the wide-spread use of such holders it is important to have them of standardized. economical construction capable of low-cost mass production. l

The present invention has been developed to meet the above and other requirements while at the same time eliminating the objections mentioned and producing a simple, practicable, durable and low-cost holder of the type stated.

In order to more clearly disclose the construction, operation and use of the invention reference should be had to the accompanying drawings forming part of the present application.

Throughout the several figures of the drawings, like reference characters designate the same parts in the different views.

In the drawings- Fig. l is a front elevation of the invention, as-

' Sembled:

Fig. 2 is a right hand side elevation of Fig. l; Fig. 3 is a bottom plan view of Fig. 1; Fig. 4 is a rear view of the front plate of Fig. 1; -Fig. 5 is a front elevation of the ceramic frame or body of the holder;

Fig. 6 is a front elevation of one of the electrodes; and

Fig. 7 is a cross section on line 1-1 of Fig. 1, enlarged.

In the preferred construction and arrangement a pair of side plates or walls I of beryllium copper or other substantially equivalent material are amended April 30, 1928; 370 0. G. 757) provided each with .a suitable plug-in terminal 2, the terminals being carried by ears 3 deflected at approximate right angles to the plates and. in assembled relation, extending across beneath the parts secured between the plates. The terminals 2 may be soldered to ears 3 or connected thereto in any other acceptable manner. The plates are right and left, relatively to each other, or, complementary.

Between these plates is disposed a chase or frame 4 in the form of a, hollow rectangle of ceramic material. Within this chase 4 and between plates I, when assembled, are disposed the two electrode plates 5, the crystal 6 and the coil spring l, assembled in usual and well-known manner.

Electrode plates 5 are provided with slightly raised triangular corner areas or lands 8. When the two electrodes are disposed with their corners 8 engaged. throughout, their corresponding faces will be spaced apart, as will be obvious. In use, the crystal 64 is clamped between the corners 8 and thereby held in the space between the electrodes with the desired complete freedom to vibrate. The plates and crystal make up a sandwich assembly. The opening 9 in chase I is, of course, proportioned to properly receive the sandwich assembly of electrode plates, crystal and spring.

There are many ways, of course, of maintaining the various parts assembled as a complete and finished unit ready to be plugged in in usual and well known manner.

The preferred construction and arrangement of this invention for maintaining this assembly is that of cooperating rib and groove, the respective rib and groove surfaces being adequately soldered providing a complete weather proof seal throughout. In the construction shown, the vertical Walls or faces of the ceramic chase are provided with continuousgrooves I0 completely surrounding the opening 9. Since certain solders, especially lead solders, will not adhere to ceramic materials the surfaces of and adjacent to grooves I0 are platinized or otherwise treated, as at II, in well known manner to assure secure soldering action As will be well understood, the ceramic chase of this invention may be molded or extruded and, therefore, may be readily produced in any desired size to receive any desired size of electrode and crystal assembly. It is then only necessary to make the plates l of corresponding size which, again, is easilydone. Since the terminals are soldered to plates I they become integral therewith, thereby reducing the number of parts to that extent. Soldering, in accordance with this invention makes the assembled unit weather proof and results in a complete hermetic seal, thereby eliminating necessity for a separate enclosing housing.

From the above it Will be evident that the present invention greatly reduces the number of parts, requiring only the minimum or near minimum.

The ceramic chase and metal plates become, to all intents and purposes, an integral, hermetically sealed, weather proof unit containing and protecting the crystal and immediately associated parts.

In assembling the invention in production any acceptable jig will be used. The several parts properly arranged will be put in the jig. liminary to assembling in the jig the ribs i 2 may be tinned in well known m'anner, with sufl* cient excess to assure the desired soldering connection. Or a ribbonor strip of solder may be seated in grooves I as the parts are put in the jig. Then the assembled parts, in the jig, will be put under suncient pressure to form the unit,

`the spring 1 being maintained under proper compression. In this state suflicient heat will be applied, in well known manner, to melt the solder. Then, after the solder has set, the jig will be opened. 'I'he resulting product embodying the invention, is a permanently integral unit, as above described comprising approximately the minimum number of parts and produced at a greatly reduced cost with a great saving in time.

It is believed that the construction, operation and use of the invention will be clear from the preceding detailed description.

Changes may be made in the construction, arrangement and disposition of the various parts of the invention within the scope of the appended claims Without departing from the eld of the invention, and it is meant to include all such within this application wherein only one preferred form has been illustrated purely by way of example and with no thought or intention of, in any degree. limiting the invention thereby.

Having thus described my invention what I claim and desire to protect by Letters Patent isf 1. A crystal holder comprising a hollow rectangular ceramic chase having a pair of substantially parallel faces transverse thereto. a central opening in each of said faces extending through said chase, soldering grooves about said openings, electrode plates mounted within said chase, a crystal clamped between said electrodes, metal plates closing said openings and provided with plug-in terminals and with ribs cooperat- Preing with the aforesaid soldering grooves, said grooves and ribs being continuously soldered throughout their lengths providing hermetic sealing between said plates and chase completelyl about the opening through said chase.

2. A crystal holder comprising a hollow chase provided witha central opening therethrough and having faces substantially perpendicular to said opening, one of said faces having a cir- .cumferential solder groove, a crystal and electrode plate sandwich unit disposed within the opening in said chase, metal plates confining said unit within said opening, one of said plates being provided with a rib complementary to aforesaid; groove and seated therein, said chase and plates being integrally connected.

4. A crystal holder comprising a hollow chase provided with a central opening therethrough and having faces substantially perpendicular` to said opening', said faces having circumferential solder grooves, a crystal and electrode plate sandwich unit disposed within the opening in'said chase, metal plates confining said unit within said opening, said plates being provided with ribs complementary to the aforesaid grooves and seated therein, said chase and plates being integrally connected an'd a pressure device conned between said sandwich and the remote plate and yieldingly maintaining said sandwich unit against the adjacent plate.

. 5. A crystal holder comprising a hollow chase provided with a central opening therethrough and having faces substantially perpendicular to said opening, one of said faces having a. circumferential solder groove, a crystal and electrode plate sandwich unit disposed within said opening, plates confining said unit within said opening. said plates being provided with integrally formed plug-in terminals, one of said plates being provided with a rib complementary to and seated in said groove and means integrally connecting said chase and said plates.

NEIL A. NELSON.

REFERENCES CITED The following references'are of record in "the le of this patent:

UNITED STATES PATENTSv Number Name Date 2,361,343 Woodmark Oct. 24, 1944 2,327,487 Bach Aug. 24, 1943 

